Methods for cooling bodies, such as objects, in gases is known. For example, objects are cooled in commonly-used refrigerators and freezers by contact with cooled air. The air is cooled by passing relatively warm air over a heat exchanger in which there is a cooler fluid. The fluid is cooled by evaporative cooling of a low boiling liquid, e.g. a CFC or HCFC fluorocarbon, in a closed cycle system.
Methods for cooling gases and liquids are also known, apart from evaporative cooling. One method involves bubbling gas though a cool liquid. For example, M. A. Krongold, in U.S. Pat. No. 4,607,489, which issued Aug. 26, 1986, discloses cooling gas by bubbling the gas through a cryogenic liquid. B. Adolfsson, in PCT Publication WO95/09124, published Apr. 6, 1995, discloses introducing carbon dioxide below the surface of a liquid, wherein the expansion of the carbon dioxide cools the liquid.
The phenomenon of cooling gases by their expansion is known. The present invention utilizes this phenomenon to cool a target such as bodies or chambers, preferably without the necessity of closed cycle systems or environmentally or physiologically problematic materials such as CFCs or HCFCs.